Liquid chromatography technique

ABSTRACT

Liquid chromatography techniques are disclosed. Specifically, the liquid chromatography technique includes providing a liquid chromatography system having a coated metallic fluid-contacting element, and transporting a fluid to contact the coated metallic fluid-contacting element. Conditions for the transporting of the fluid are selected from the group consisting of the temperature of the fluid being greater than 150° C., pressure urging the fluid being greater than 60 MPa, the fluid having a protein-containing analyte incompatible with one or both of titanium and polyether ether ketone, the fluid having a chelating agent incompatible with the one or both of the titanium or the polyether ether ketone, and combinations thereof

PRIORITY

The present application is a continuation application, which claimspriority and benefit of Non-Provisional patent application Ser. No.16/971,216, currently pending, which is a 371 National Stage Applicationof International Application PCT/US2019/019209, titled “LIQUIDCHROMATOGRAPHY TECHNIQUE”, filed Feb. 22, 2019, which claims priorityand benefit of U.S. Provisional Patent Application No. 62/634,299, filedFeb. 23, 2018, and titled “LIQUID CHROMATOGRAPHY TECHNIQUE,” each ofwhich are incorporated by reference in tehri entirety.

FIELD OF THE INVENTION

The present invention is directed to liquid chromatography techniques.More particularly, the present invention is directed to liquidchromatography techniques utilizing a coated metallic fluid-contactingelement.

BACKGROUND OF THE INVENTION

Analytical instrumentation is a constantly evolving field. There areconstant desires to become quicker, smaller, more precise, and moreaccurate. However, such desires create limitations that have not beenphysically possible with existing materials.

For example, titanium is used in high performance (or pressure) liquidchromatography (HPLC). However, under certain conditions, titanium isincompatible with ammonia, chlorine (both wet and dry), HCl, nitratingacid (nitric and sulfuric combination), phosphoric acid, sodium andpotassium hydroxide, bleach, and sulfuric acid. Titanium is alsobrittle, limiting the ability to bend it, for example, into tubing.Also, titanium is very expensive, resulting it being unavailable forcost-effective techniques.

In contrast, polyether ether ketone (PEEK) is flexible and inexpensive.However, PEEK has many other drawbacks. Under certain conditions, PEEKis incompatible with benzene sulfonic acid, chlorine (both wet and dry),nitric acid, sulfuric acid, carbolic acid, ultraviolet light, methylenechloride, dimethylsulfate, tetrahydrofuran, and other organic solvents.PEEK also has an upper temperature limit of between 100° C. and 143° C.,depending upon the application.

A liquid chromatography technique, system, and components, that show oneor more improvements in comparison to the prior art would be desirablein the art.

BRIEF DESCRIPTION OF THE INVENTION

In an embodiment, a liquid chromatography technique includes providing aliquid chromatography system having a coated metallic fluid-contactingelement, and transporting a fluid to contact the coated metallicfluid-contacting element. Conditions for the transporting of the fluidare selected from the group consisting of the temperature of the fluidbeing greater than 150° C., pressure urging the fluid being greater than60 MPa, the fluid having a protein-containing analyte incompatible withone or both of titanium and polyether ether ketone, the fluid having achelating agent incompatible with the one or both of the titanium or thepolyether ether ketone, and combinations thereof.

In another embodiment, a liquid chromatography technique includesproviding a liquid chromatography system having a coated metalliccolumn, a degasser, a sample, one or more pumps, and a detector. Theliquid chromatography technique further includes transporting a fluidthrough the coated metallic column, wherein conditions for thetransporting of the fluid include one or both of the fluid having aprotein-containing analyte incompatible with one or both of titanium andpolyether ether ketone, and the fluid having a chelating agentincompatible with the one or both of the titanium or the polyether etherketone.

In another embodiment, a liquid chromatography technique includesproviding a liquid chromatography system having a coated metalliccolumn, a stationary phase being positioned within the coated metalliccolumn, the stationary phase including particles having a size of lessthan 1.5 micrometers. The liquid chromatography technique furtherincludes transporting a fluid through the coated metallic column,wherein conditions for the transporting of the fluid include thetemperature of the fluid being greater than 150° C., pressure urging thefluid within the coated metallic column being greater than 60 MPa, thefluid having a protein-containing analyte incompatible with one or bothof titanium and polyether ether ketone, the fluid having a chelatingagent incompatible with the one or both of the titanium or the polyetherether ketone, and combinations thereof. The coated metallic column has acoating including carbon, silicon, oxygen, and hydrogen, and a stainlesssteel substrate, the pH of the fluid is less than 2, the coated metalliccolumn has a diameter of less than 2.1 mm, the coated metallic columnhas a length of less than 20 cm, and the coated metallic component has acoating having a thickness of at least 400 nm. The transporting of thefluid through the coated metallic column is at a linear velocity of atleast 8 mm per second. The fluid includes a solvent selected from thegroup consisting of water, acetonitrile, methanol, formic acid,phosphoric acid, tetrahydrofuran, trifluoroacetic acid, and combinationsthereof. The fluid includes an analyte selected from the groupconsisting of tetracycline, N-hydroxypyridine-2-on, adenosinetriphosphate, and deoxynucleotide monophosphate.

Other features and advantages of the present invention will be apparentfrom the following more detailed description, taken in conjunction withthe accompanying drawings which illustrate, by way of example, theprinciples of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a liquid chromatography system forperforming an embodiment of a liquid chromatography technique, accordingto the disclosure.

FIG. 2 is a schematic perspective view of a column for a liquidchromatography system capable of performing an embodiment of the liquidchromatography technique, according to the disclosure.

Wherever possible, the same reference numbers will be used throughoutthe drawings to represent the same parts.

DETAILED DESCRIPTION OF THE INVENTION

Provided are liquid chromatography techniques, systems, and components.Embodiments of the present disclosure, for example, in comparison toconcepts failing to include one or more of the features disclosedherein, expands the capabilities of liquid chromatography, permitsincreased precision of liquid chromatography, permits increased accuracyof liquid chromatography, permits decreased sizes of columns to be usedin liquid chromatography, permits reduced duration of analysis forliquid chromatography, permits bioinert and/or protein anti-stictionoperation of liquid chromatography, permits operations with fluidsincompatible with titanium under certain conditions (for example,ammonia, chlorine (both wet and dry), HC1, nitrating acid (nitric andsulfuric combination), phosphoric acid, sodium and potassium hydroxide,bleach, and sulfuric acid), permits operation with fluids incompatiblewith polyether ether ketone (for example, benzene sulfonic acid,chlorine (both wet and dry), nitric acid, sulfuric acid, carbolic acid,ultraviolet light, methylene chloride, dim ethyl sulfate,tetrahydrofuran, and other organic solvents), permits liquidchromatography to be performed at higher pressures, permits liquidchromatography to be performed at higher temperatures, permits liquidchromatography to be performed with smaller particles in the stationaryphase, permits liquid chromatography to be performed with smallerdiameter and/or length columns, or permit a combinations thereof.

Referring to FIG. 1, a liquid chromatography technique, utilizing aliquid chromatography system 100, is disclosed. It will be appreciatedby those skilled in the art that the liquid chromatography technique iscapable of being used with any suitable configuration of the liquidchromatography system 100. Such suitable configurations include, but arenot limited to high performance (or pressure) liquid chromatography(HPLC), ultra high performance (or pressure) liquid chromatography(UHPLC), partitioned HPLC or UHPLC, normal-phase chromatography,displacement chromatography, reversed-phase chromatography, sizeexclusion chromatography, ion-exchange chromatography, or a combinationthereof.

Referring again to FIG. 1, an exemplary system 100 includes solventreservoirs 101, a solvent degasser 102, a gradient valve 103, a mixingvessel 104 for delivery of a mobile phase, a high-pressure pump 105,switching valves 106 in injection position or loading position, a sampleinjection loop 107, a pre-column portion 108, a coated metallic column109, a detector 110 (for example, an infrared detector or ultravioletdetector), a data acquisition system 111 (for example, a computer), anda waste or fraction collector 112. Any additional or alternativecomponents are capable of being used, so long as the system 100 includesa coated metallic fluid-contacting element, such as the coated metalliccolumn 109, or any other component of the system 100 that is contactedby a fluid, such as, a mobile phase, a solvent, an analyte, or acombination thereof Additionally or alternatively, other components arecapable of being similarly coated, such as, frits, fittings, pump heads,valves, tubing, vessels, or combinations thereof.

Referring to FIG. 2, in one embodiment, the coated metallic column 109contains particles 205 or beads. The particles 205 serve as a stationaryphase during the liquid chromatography technique. The particles 205 havea size (for example, a diameter and/or width) that is less than 10micrometers, less than 6 micrometers, less than 5 micrometers, less than3 micrometers, less than 2 micrometers, less than 1.7 micrometers, lessthan 1.5 micrometers, between 1 micrometer and 10 micrometers, between 1micrometer and 5 micrometers, between 1 micrometer and 3 micrometers,between 1 micrometer and 2 micrometers, 0.67 micrometers, less than 0.67micrometers, or any suitable combination, sub-combination, range, orsub-range therein. In one embodiment, the particles 205 are hydrophobicand/or porous. A coating 203 on the coated metallic column 109 permitsthe particles 205 having such dimensions and features to be used duringthe liquid chromatography technique. Suitable thicknesses of the coating203 include, but are not limited to, at least 50 nm, at least 100 nm, atleast 200 nm, at least 300 nm, at least 400 nm, at least 600 nm, atleast 800 nm, at least 1,000 nm, at least 1,200 nm, between 50 nm and1,600 nm, between 400 nm and 1,600 nm, between 1,000 nm and 1,600 nm, orany suitable combination, sub-combination, range, or sub-range therein.

Suitable lengths for the coated metallic column 109 include, but arelimited to, between 10 cm and 20 cm, between 10 cm and 50 cm, 15 cm,greater than 10 cm, greater than 14 cm, less than 20 cm, less than 16cm, between 10 cm and 400 cm, between 10 cm and 100 cm, greater than 100cm, greater than 250 cm, or any suitable combination, sub-combination,range, or sub-range therein.

Suitable diameters (or widths) for the coated metallic column 109include, but are limited to, less than 2.1 mm, less than 1.7 cm, lessthan 1.5 cm, less than 0.3 mm, or any suitable combination,sub-combination, range, or sub-range therein.

The coated metallic column 109 includes a substrate 201 and the coating203. The substrate 201 is a metallic material, such as stainless steel.Suitable stainless steels include 304 stainless steel and 316 stainlesssteel. Any other metallic material compatible with the operationalconditions of the liquid chromatography technique are suitable. Suitablemetallic materials include, but are not limited to, ferrous-basedalloys, non-ferrous-based alloys, nickel-based alloys, stainless steels(martensitic or austenitic), aluminum alloys, composite metals, orcombinations thereof.

In one embodiment, the metallic material is or includes a composition,by weight, of up to 0.08% carbon, between 18% and 20% chromium, up to 2%manganese, between 8% and 10.5% nickel, up to 0.045% phosphorus, up to0.03% sulfur, up to 1% silicon, and a balance of iron (for example,between 66% and 74% iron).

In one embodiment, the metallic material is or includes a composition,by weight, of up to 0.08% carbon, up to 2% manganese, up to 0.045%phosphorus, up to 0.03% sulfur, up to 0.75% silicon, between 16% and 18%chromium, between 10% and 14% nickel, between 2% and 3% molybdenum, upto 0.1% nitrogen, and a balance of iron.

In one embodiment, the metallic material is or includes a composition,by weight, of up to 0.03% carbon, up to 2% manganese, up to 0.045%phosphorus, up to 0.03% sulfur, up to 0.75% silicon, between 16% and 18%chromium, between 10% and 14% nickel, between 2% and 3% molybdenum, upto 0.1% nitrogen, and a balance of iron.

In one embodiment, the metallic material is or includes a composition,by weight, of between 14% and 17% chromium, between 6% and 10% iron,between 0.5% and 1.5% manganese, between 0.1% and 1% copper, between0.1% and 1% silicon, between 0.01% and 0.2% carbon, between 0.001% and0.2% sulfur, and a balance nickel (for example, 72%).

In one embodiment, the metallic material is or includes a composition,by weight, of between 20% and 24% chromium, between 1% and 5% iron,between 8% and 10% molybdenum, between 10% and 15% cobalt, between 0.1%and 1% manganese, between 0.1% and 1% copper, between 0.8% and 1.5%aluminum, between 0.1% and 1% titanium, between 0.1% and 1% silicon,between 0.01% and 0.2% carbon, between 0.001% and 0.2% sulfur, between0.001% and 0.2% phosphorus, between 0.001% and 0.2% boron, and a balancenickel (for example, between 44.2% and 56%).

In one embodiment, the metallic material is or includes a composition,by weight, of between 20% and 23% chromium, between 4% and 6% iron,between 8% and 10% molybdenum, between 3% and 4.5% niobium, between 0.5%and 1.5% cobalt, between 0.1% and 1% manganese, between 0.1% and 1%aluminum, between 0.1% and 1% titanium, between 0.1% and 1% silicon,between 0.01% and 0.5% carbon, between 0.001% and 0.02% sulfur, between0.001% and 0.02% phosphorus, and a balance nickel (for example, 58%).

In one embodiment, the metallic material is or includes a composition,by weight, of between 25% and 35% chromium, between 8% and 10% iron,between 0.2% and 0.5% manganese, between 0.005% and 0.02% copper,between 0.01% and 0.03% aluminum, between 0.3% and 0.4% silicon, between0.005% and 0.03% carbon, between 0.001% and 0.005% sulfur, and a balancenickel (for example, 59.5%).

In one embodiment, the metallic material is or includes a composition,by weight, of between 17% and 21% chromium, between 2.8% and 3.3% iron,between 4.75% and 5.5% niobium, between 0.5% and 1.5% cobalt, between0.1% and 0.5% manganese, between 0.2% and 0.8% copper, between 0.65% and1.15% aluminum, between 0.2% and 0.4% titanium, between 0.3% and 0.4%silicon, between 0.01% and 1% carbon, between 0.001 and 0.02% sulfur,between 0.001 and 0.02% phosphorus, between 0.001 and 0.02% boron, and abalance nickel (for example, between 50% and 55%).

In one embodiment, the metallic material is or includes a composition,by weight, of between 2% and 3% cobalt, between 15% and 17% chromium,between 5% and 17% molybdenum, between 3% and 5% tungsten, between 4%and 6% iron, between 0.5% and 1% silicon, between 0.5% and 1.5%manganese, between 0.005 and 0.02% carbon, between 0.3% and 0.4%vanadium, and a balance nickel.

In one embodiment, the metallic material is or includes a composition,by weight, of up to 0.15% carbon, between 3.5% and 5.5% tungsten,between 4.5% and 7% iron, between 15.5% and 17.5% chromium, between 16%and 18% molybdenum, between 0.2% and 0.4% vanadium, up to 1% manganese,up to 1% sulfur, up to 1% silicon, up to 0.04% phosphorus, up to 0.03%sulfur, and a balance nickel.

In one embodiment, the metallic material is or includes a composition,by weight, of up to 2.5% cobalt, up to 22% chromium, up to 13%molybdenum, up to 3% tungsten, up to 3% iron, up to 0.08% silicon, up to0.5% manganese, up to 0.01% carbon, up to 0.35% vanadium, and a balancenickel (for example, 56%).

In one embodiment, the metallic material is or includes a composition,by weight, of between 1% and 2% cobalt, between 20% and 22% chromium,between 8% and 10% molybdenum, between 0.1% and 1% tungsten, between 17%and 20% iron, between 0.1% and 1% silicon, between 0.1% and 1%manganese, between 0.05 and 0.2% carbon, and a balance nickel.

In one embodiment, the metallic material is or includes a composition,by weight, of between 0.01% and 0.05% boron, between 0.01% and 0.1%chromium, between 0.003% and 0.35% copper, between 0.005% and 0.03%gallium, between 0.006% and 0.8% iron, between 0.006% and 0.3%magnesium, between 0.02% and 1% silicon+iron, between 0.006% and 0.35%silicon, between 0.002% and 0.2% titanium, between 0.01% and 0.03%vanadium+titanium, between 0.005% and 0.05% vanadium, between 0.006% and0.1% zinc, and a balance aluminum (for example, greater than 99%).

In one embodiment, the metallic material is or includes a composition,by weight, of between 0.05% and 0.4% chromium, between 0.03% and 0.9%copper, between 0.05% and 1% iron, between 0.05% and 1.5% magnesium,between 0.5% and 1.8% manganese, between 0.5% and 0.1% nickel, between0.03% and 0.35% titanium, up to 0.5% vanadium, between 0.04% and 1.3%zinc, and a balance aluminum (for example, between 94.3% and 99.8%).

In one embodiment, the metallic material is or includes a composition,by weight, of between 0.0003% and 0.07% beryllium, between 0.02% and 2%bismuth, between 0.01% and 0.25% chromium, between 0.03% and 5% copper,between 0.09% and 5.4% iron, between 0.01% and 2% magnesium, between0.03% and 1.5% manganese, between 0.15% and 2.2% nickel, between 0.6%and 21.5% silicon, between 0.005% and 0.2% titanium, between 0.05% and10.7% zinc, and a balance aluminum (for example, between 70.7% to98.7%).

In one embodiment, the metallic material is or includes a composition,by weight, of between 0.15% and 1.5% bismuth, between 0.003% and 0.06%boron, between 0.03% and 0.4% chromium, between 0.01% and 1.2% copper,between 0.12% and 0.5% chromium+manganese, between 0.04% and 1% iron,between 0.003% and 2% lead, between 0.2% and 3% magnesium, between 0.02%and 1.4% manganese, between 0.05% and 0.2% nickel, between 0.5% and 0.5%oxygen, between 0.2% and 1.8% silicon, up to 0.05% strontium, between0.05% and 2% tin, between 0.01% and 0.25% titanium, between 0.05% and0.3% vanadium, between 0.03% and 2.4% zinc, between 0.05% and 0.2%zirconium, between 0.150 and 0.2% zirconium+titanium, and a balance ofaluminum (for example, between 91.7% and 99.6%).

In one embodiment, the metallic material is or includes a composition,by weight, of between 0.4% and 0.8% silicon, up to 0.7% iron, between0.15% and 0.4% copper, up to 0.15% manganese, between 0.8% and 1.2%magnesium, between 0.04% and 0.35% chromium, up to 0.25% zinc, up to0.15% titanium, optional incidental impurities (for example, at lessthan 0.05% each, totaling less that 0.15%), and a balance of aluminum(for example, between 95% and 98.6%).

In one embodiment, the metallic material is or includes a composition,by weight, of between 11% and 13% silicon, up to 0.6%impurities/residuals, and a balance of aluminum.

The coating 203 includes one or a plurality of depositions,decompositions, functionalizations, oxidations, or a combinationthereof. In one embodiment, the coating 203 includes carbon, silicon,oxygen, and hydrogen. In additional or alternative embodiments, otherconstituents in the coating 203 include, but are not limited to,fluorine, nitrogen, decompositional materials from precursor materials,thnctionalizations from precursor materials, or a combination thereof.Suitable precursor materials include, but are not limited to, silane,silane and ethylene, silane and an oxidizer, dimethylsilane,dimethylsilane and an oxidizer, trimethylsilane, trimethylsilane and anoxidizer, dialkylsilyl dihydride, alkylsilyl trihydride, non-pyrophoricspecies (for example, dialkylsilyl dihydride and/or alkylsilyltrihydride), thermally-reacted material (for example, carbosilane and/orcarboxysilane, such as, amorphous carbosilane and/or amorphouscarboxysilane), species capable of a recombination of carbosilyl(disilyl or trisilyl fragments), methyltrimethoxysilane,methyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane,trimethylmethoxysilane, trimethylethoxysilane, ammonia, hydrazine,trisilylamine, Bis(tertiary-butylamino)silane,1,2-bis(dimethylamino)tetramethyldisilane, dichlorosilane,hexachlorodisilane), organofluorotrialkoxysilane,organofluorosilylhydride, organofluoro silyl, fluorinated alkoxysilane,fluoroalkylsilane, fluorosilane, tridecafluoro1,1,2,2-tetrahydrooctylsilane, (tridecafluoro-1,1,2,2-tetrahydrooctyl)triethoxysilane, triethoxy(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-1-octyl) silane,(perfluorohexylethyl) triethoxysilane, silane(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl) trimethoxy-,or a combination thereof.

The liquid chromatography technique includes a fluid transported throughthe coated metallic column 109, for example, passing through theparticles 205 serving as the stationary phase for the liquidchromatography technique. The fluid is or includes the mobile phase, oneor more solvents, one or more analytes, or a combination thereofSuitable species of the fluid include, but are not limited to aprotein-containing analyte incompatible with one or both of titanium andpolyether ether ketone and a chelating agent incompatible with the oneor both of the titanium or the polyether ether ketone. Specific solventscapable of being used within the liquid chromatography techniqueinclude, but are not limited to, water, acetonitrile, methanol, formicacid, phosphoric acid, tetrahydrofuran, trifluoroacetic acid, andcombinations thereof. Specific analytes capable of being used within theliquid chromatography technique include, but are not limited to,tetracycline, N-hydroxypyridine-2-on, adenosine triphosphate, anddeoxynucleotide monophosphate.

In one embodiment, the liquid chromatography technique includes thefluid being at a temperature not suitable for polyether ether ketoneand/or titanium, for example, in conjunction with other operationalparameters of the liquid chromatography technique. Such temperaturesinclude, but are not limited to, between 100° C. and 200° C., between200° C. and 300° C., between 300° C. and 400° C., between 400° C. and450° C., greater than 150° C., greater than 200° C., greater than 250°C., greater than 300° C., greater than 350° C., greater than 400° C., orany suitable combination, sub-combination, range, or sub-range therein.

In one embodiment, the liquid chromatography technique includes thefluid being urged by a pressure not suitable for polyether ether ketoneand/or titanium, for example, in conjunction with other operationalparameters of the liquid chromatography technique. Such pressuresinclude, but are not limited to, between 10 MPa and 150 MPa, 30 Mpa and150 MPa, 50 MPa and 100 MPa, between 100 MPa and 150 MPa, between 100MPa and 200 MPa, or any suitable combination, sub-combination, range, orsub-range therein.

In one embodiment, the liquid chromatography technique includes thefluid being at a pH value not suitable for polyether ether ketone and/ortitanium, for example, in conjunction with other operational parametersof the liquid chromatography technique. Such pH values include, but arenot limited to, less than 3, less than 2, less than 1, greater than 9,greater than 10, greater than 12, between 0 and 3, between 9 and 14,between 0 and 14, or any suitable combination, sub-combination, range,or sub-range therein.

In one embodiment, the liquid chromatography technique includes thefluid being transported at a linear velocity not suitable for polyetherether ketone and/or titanium, for example, in conjunction with otheroperational parameters of the liquid chromatography technique. Suchlinear velocities include, but are not limited to, between 1 and 9 mmper second, between 3 and 9 mm per second, at least 3 mm per second, atleast 8 mm per second, or any suitable combination, sub-combination,range, or sub-range therein.

While the invention has been described with reference to one or moreembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the scope of the invention. Inaddition, many modifications may be made to adapt a particular situationor material to the teachings of the invention without departing from theessential scope thereof. Therefore, it is intended that the inventionnot be limited to the particular embodiment disclosed as the best modecontemplated for carrying out this invention, but that the inventionwill include all embodiments falling within the scope of the appendedclaims. In addition, all numerical values identified in the detaileddescription shall be interpreted as though the precise and approximatevalues are both expressly identified.

What is claimed is:
 1. A liquid chromatography technique, comprising:providing a liquid chromatography system having a coated stainless steelfluid-contacting element; and transporting a fluid to contact the coatedstainless steel fluid-contacting element; wherein the fluid includesadenosine triphosphate; wherein the coated stainless steelfluid-contacting element has a coating, the coating including carbon,silicon, oxygen, and hydrogen.
 2. The technique of claim 1, wherein thecoated stainless steel fluid-contacting element is a frit.
 3. Thetechnique of claim 1, wherein the coated stainless steelfluid-contacting element is a fitting.
 4. The technique of claim 1,wherein the coated stainless steel fluid-contacting element is a pumphead.
 5. The technique of claim 1, wherein the coated stainless steelfluid-contacting element is a valve.
 6. The technique of claim 1,wherein the liquid chromatography system has a stationary phase, thestationary phase having particles having a size of less than 6micrometers.
 7. The technique of claim 1, wherein the liquidchromatography system has a stationary phase, the stationary phasehaving particles being hydrophobic.
 8. The technique of claim 1, whereinthe liquid chromatography system includes a solvent reservoir, a solventdegasser, a gradient valve, a mixing vessel, a high-pressure pump,switching valves, a sample injection loop, a pre-column portion, acoated metallic column, a detector, a data acquisition system, and awaste collector.
 9. The technique of claim 1, wherein the liquidtechnique is high performance liquid chromatography.
 10. The techniqueof claim 1, wherein the liquid technique is ultra high performanceliquid chromatography.
 11. The technique of claim 1, wherein the liquidtechnique is partitioned high performance liquid chromatography.
 12. Thetechnique of claim 1, wherein the liquid technique is partitioned ultrahigh performance liquid chromatography.
 13. The technique of claim 1,wherein the liquid technique is normal-phase chromatography.
 14. Thetechnique of claim 1, wherein the liquid technique is displacementchromatography.
 15. The technique of claim 1, wherein the liquidtechnique is reversed-phase chromatography.
 16. The technique of claim1, wherein the liquid technique is size exclusion chromatography. 17.The technique of claim 1, wherein the liquid technique is ion-exchangechromatography.
 18. A liquid chromatography technique, comprising:transporting adenosine triphosphate in a liquid chromatography system,the liquid chromatography having a frit, a fitting, a valve, and a pumphead; wherein the at least one of the frit, the fitting, the valve, andthe pump head have a coating, the coating including carbon, silicon,oxygen, and hydrogen.
 19. The technique of claim 18, wherein each of thefrit, the fitting, the valve, and the pump head have the coating.
 20. Aliquid chromatography technique, comprising: providing a liquidchromatography system having a coated stainless steel fluid-contactingelement; and transporting a fluid to contact the coated stainless steelfluid-contacting element; wherein the fluid includes tetracycline.